RISING CONTROL OF EXTRUDER

• Main Authors: SHIRAHATA NORIO, NAKAMURA YOSHINORI
• Format: Patent
• Language: English
• Published: 10.05.1985
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; BASIC ELECTRIC ELEMENTS; CABLES; CONDUCTORS; ELECTRICITY; INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULARARTICLES; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; INSULATORS; PERFORMING OPERATIONS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING ORDIELECTRIC PROPERTIES; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

PURPOSE:To enable reduction in the loss of material with a shortened time from the starting of operation to the withdrawal of a product by setting the heating temperature higher than the normal value in the rising of a foam plastic cover extruder to raise the revolutions of a screw at a higher rate. CONSTITUTION:The set heating temperature value of an extruder is set higher than the normal value as far as no excessive foaming of the resin takes place, the extruder is started and then, the value is returned to the normal when it approaches the proper value. The takeoff speed of an extruded matter after the starting is controlled to rise at a constant rate but at this time, the revolutions of the screw are raised faster than the takeoff speed up to the normal value as far as no excessive pressure in the resin takes place. Thus, the time at which the takeoff time speed reaches the normal value can almost coincide with the time T2 at which the resin temperature reaches the proper value to permit the withdrawal of a product thereby significantly reducing the tine length from the starting to the withdrawal of a product.